U 84, U 93, and U 95 all sailed within a few days of each other — Jan. 1, 1918, Dec. 29, 1917, and Dec. 27, 1917 respectively — from Germany. We also know that all three of these boats successfully got through the Straits of Dover outbound.

First of all, U 95 is not an option for a Bay of Biscay POW rescue mission. Per Spindler, U 95's patrol area was the western English Channel (Spindler V, p. 45).

In recent years, the wrecks of three large U-boats have been found. The first located is off Hardelot. I was among the people involved in trying to identify this wreck. The submarine in question is of the U 93 type. (By design, could be U 93, U 95, or U 109). It was clearly lost while homebound and has massive damage to the stern (internal torpedo explosion?). The propellers were scrubbed and clearly exclude U 109. Based upon dates on the props, Axel Niestle concluded that the wreck was most likely that of U 95 (dates after U 93 was launched but before U 95 was launched). The January 16, 1918 date was the apparent last contact date from RN files (but further west). This is what this site's listing reflects.

Then, a few years later, Innes McCartney dived a U 93 class wreck near the Lizard. Innes was under the opinion that the wreck off the Lizard is likely U 95 and sunk on January 7, 1918 by ramming. (This was the attribution for U 95 before the Hardelot wreck was found.) The Hardelot wreck, despite the propeller markings must thus be U 93. The RN January 16th mention could easily be a misattribution or otherwise made in error. Also, from an operational prospective, the odds are higher that U 93, with its patrol area along the French coast, would return via Dover as compared to U 95, which was assigned to operate in the western English Channel.

Innes’ hypothesis is pretty strong. However, the alternative theory would be that the Lizard wreck is that of U 109. (It's hard to get U 93 to off the Liard.) The wreck Innes found is within a mile of a RN minefield. The sinking claim for U 109 is via mine off Griz Nez while sailing outboard through Dover on January 26th, 1918. Upon closer examination, there really isn’t all that strong of a sinking claim there. U 109’s patrol area was the St. George Channel, and the Lizard would be along the way for her.

Finally, the wreck of U 84 was found off Penmarch about three years ago. I was involved in identifying that wreck. One area of particular concern was making sure the wreck was not U 93 — and based upon certain design characteristics, we ultimately determined the wreck had to be U 84, not U 93.